Blown head gasket?

[lowpost99]

I'm looking for the cause of my loss of coolant. I'm losing about a gallon of coolant every 4-5 days and none of it is in the engine bay or on the ground. I'm not overheating, or driving roughly, no coolant in the oil drained while cold. The previous kerosene flush/oil change was due to a gunky chocolate milkshake colored muck in the cam covers, but I haven't seen a sign it again since. I also started experiencing random and varying losses of oil after changing my catalytic converters about two years ago. What's the best method to use to check our trucks for a head gasket leaks? Can I remove the fuel pump and starter fuses and crank the car with one plug in each cylinder at a time to see if it spits coolant at the reservoir? I've seen several videos on testing for blown head gasket and they tested at the radiator cap several ways for compression gases, can I do all of these tests just at the reservoir? Could there be another cause for the loss of coolant? Is this a good candidate for BARS professional head gasket repair fluid?

 

[swathdiver]

You can pressure test the radiator and watch the coolant tank. Run a compression test on each cylinder and a leakdown test to further solidify findings. Not sure about repair fluids. There's another method I recently learned about on here that escapes me at the moment. Others will chime in.

 

[iamdub]

First off- PLEASE do NOT put any "stop leak" gunks in your engine or radiator.

As James mentioned, do a cooling system pressure test. At the rate you're losing coolant, you should notice a significant leak if you have one.

Have you ever checked the tailpipe for steam while idling? Does the engine smell of coolant when hot? Any whitish/greenish or reddish chalky traces dried on the block anywhere?

Also, if for any reason you need to crank the engine without it firing the fuel injectors, simply push and hold the throttle pedal to the floor while cranking. This is the built-in "flood-clearing" feature. No need to remove fuses, unplug ignition coils, etc.

 

[lowpost99]

So today I found a bad hose and which I fixed . Still lost pressure during the he radiator pressure test. Next I looped the heater core hoses together to see if the issue was in the heater core and I'm still losing about 1psi every 90 mins. I've checked the radiator hoses, the overflow reservoir, the water pump hoses and the pump and thermostat hoses for leaks. No coolant on the ground or on belts. Any thoughts here on what to check next. Leakdown test?

 

[SnowDrifter]

3 tests you can do here:

1. Block test. It verifies or denies the presence of exhaust gas in the coolant.

2. Leakdown test. This would find items such as a cylinder wall leak that's causing blowby into a companion cylinder

3. Oil analysis to check for coolant in the oil, prior to reaching amounts that would turn it 'milky'


Other areas where coolant can leak: Trans cooler, and engine oil cooler if equipped.

Some obscure areas where you can loose coolant; Crossover pipes on top of the engine, rear heater core. Cracked head around the pushrod tube.

The intake in this vehicle is dry with no coolant circulating through it.

 

[OR VietVet]

The 1 psi loss in 90 minutes is very very small. That can happen just with a worn tester. If you have an external leak you should see coolant/fluid on the ground or at least dripping and puddling elsewhere on the engine. If is internal, then for now drive it and see what occurs. White smoke out the tailpipe? Running hot? Etc......

 

[corvette744]

I'm looking for the cause of my loss of coolant. I'm losing about a gallon of coolant every 4-5 days and none of it is in the engine bay or on the ground. I'm not overheating, or driving roughly, no coolant in the oil drained while cold. The previous kerosene flush/oil change was due to a gunky chocolate milkshake colored muck in the cam covers, but I haven't seen a sign it again since. I also started experiencing random and varying losses of oil after changing my catalytic converters about two years ago. What's the best method to use to check our trucks for a head gasket leaks? Can I remove the fuel pump and starter fuses and crank the car with one plug in each cylinder at a time to see if it spits coolant at the reservoir? I've seen several videos on testing for blown head gasket and they tested at the radiator cap several ways for compression gases, can I do all of these tests just at the reservoir? Could there be another cause for the loss of coolant? Is this a good candidate for BARS professional head gasket repair fluid?

Your going thru a gallon of coolant every 4-5 days and show no signs of leaking on the ground or milkshake in the oil or big clouds of smoke out the tailpipe.Sounds impossible to me.IF their are no major drips on the ground and you are really putting in that much coolant you have a massive leak internal and should lose way more than 1 psi in 90 minutes-your doing something wrong.Might want to pay someone to test for your leak before you have to replace your engine.

 

[OR VietVet]

If is leaking internally the size of the leak may increase with temp but I still feel that the bad ju ju should have already reared it's ugly head by now with that much coolant loss. Something is wrong in the details I feel.

 

[Rocket Man]

You said you found a “ bad hose” and replaced it, but you’re still looking for a leak? What exactly do you mean by a bad hose? Did it have a hole and it was loosing coolant under pressure? Are you sure you didn’t fix the problem?